Jessica Simpson lost 70 pounds after giving birth by following a low-carb diet, walking and doing yoga workouts.

Jessica Simpson showed off her 70-pound weight loss in sexy Daisy Dukes in the new ad campaign for her spring 2015 Jessica Simpson Collection.

Simpson, 34, looked better than she did 10 years ago, when she first donned Daisy Dukes for the movie The Dukes of Hazzard.

In the Instagram photo, Jessica spotlighted her toned legs, courtesy of yoga, walking and a low-carb diet.

The buxom 5-foot-3 Jessica has lost more than 70 pounds since giving birth to son Ace Knute in June 2013. Simpson lost the same amount of weight six months after giving birth to daughter Maxwell in May 2012.

Simpson, a rep for Weight Watchers, has credited a low-carb diet and rigorous daily workouts for her dramatic weight loss, Examiner reported. Jessica’s diet typically features a mix of high-quality proteins like salmon and chicken and fresh vegetables and salads. Simpson also avoids processed foods and limits sugar.

For exercise, the mom of two walks a minimum of four to five miles every day (or 8,000 to 10,000 steps) and does yoga. Simpson also works out at the gym for 45 minutes, four days a week, with her longtime trainer Harley Pasternak, creator of the 5-Factor Workout DVD.

Jessica confessed her pregnancy weight gain made her depressed and demoralized. “I was so insecure; I couldn’t even believe what I weighed,” she said. “I don’t think I ever expected to see the numbers that I’ve seen on the scale.”

Pasternak and Simpson typically work out at the gym four days a week, combining 10 to 20 minutes of cardio exercise, 20 to 30 minutes of resistance training, and lots of flexibility moves.

Ironically, Jessica said her weight struggles are part of the reason she’s so successful with her clothing line, which boasts annual sales of $1 billion. Simpson said women relate to her because she’s not naturally skinny and has weight issues, just like many of them do.

“I have been every size on the planet and I understand women,” said Simpson. “I definitely go up and down with my weight, and I’m really honest about it. If I’m 5 pounds heavier, if I’m 50 pounds heavier, or 5 pounds lighter, I just don’t think it should define who you are.”